<-- Previous investigation, pre-Light stick.

Commercial Chemiluminescent Chemical Reaction With Light Stick


By: Na Young Han, Jocelyn Shih

http://scifun.chem.wisc.edu/HomeExpts/Chemilum.html



Demonstrations:


http://wow.osu.edu/experiments/chemistry/lightsticks.html

We will be activating two light sticks/glow sticks. Pass them around so everyone can feel the heat of the chemical reaction that produces light.

Safety Precautions:


1. Don't put the light stick inside hot water! The plastic will melt and your chemical reaction will be ruined.
2. Don't break the plastic and get the chemicals inside on your skin. If spilled on skin, the chemicals could cause slight skin irritation or, in extreme circumstances, cause vomiting and nausea (http://en.wikipedia.org/wiki/Glow_sticks).

Materials:


- Pack of lightsticks (different color, size, etc.)
- Fridge or ice
- Warm water
- Beakers/graduated cylinders to put the lightsticks in.
- Vernier LoggerPro Light Sensor
-Vernier LoggerPro Temperature Sensor
- Laptop with Vernier LoggerPro program
- Dark room

Plan:


Variables considered:

- Color of light stick
- Temperature light stick is immersed in
- Size of the light stick

Our Experiment:


Does temperature of the surroundings of the lightstick effect the glow?

1. Light stick in room temperature.
2. Light stick in ice water.
3. Light stick in warm water, not boiling or else plastic shell will melt.

Abstract:


Chemistry:


"The glow stick contains two chemicals and a suitable fluorescent dye (sensitizer, or fluorophor). The chemicals in the plastic tube are a mixture of the dye and Cyalume. The chemical inside the glass vial is hydrogen peroxide. By mixing the peroxide with the phenyl oxalate ester, a chemical reaction takes place; the ester is oxidized, yielding two molecules of phenol and one molecule of peroxyacid ester. The peroxyacid decomposes spontaneously to carbon dioxide, releasing energy that excites the dye, which then deexcites by releasing a photon. The wavelength of the photon—the color of the emitted light—depends on the structure of the dye." - Wikipedia (http://en.wikipedia.org/wiki/Glowstick)
external image 500px-Cyalume-reactions.svg.png

Introduction:


In this investigation, we will observe the glow of lightsticks/glowsticks. Lightsticks contain two chemicals - cyalume and hydrogen peroxide, and a fluorescent dye. We think that when the temperature is higher, the lightstick will glow brighter, because chemical reactions are faster at temperatures, and slower at lower temperatures. We think that when the reaction of the chemicals is faster, the glow will be brighter, because it uses up the reactants more quickly.

Procedure:


1, Put a few light sticks in the freezer
2. Put around 300mL of tap water in the 500mL beaker and heat it untill the water is warm
2. Put a few lightsticks in graduated cylinders filled with warm water. (Make sure the water isn't hot! The glass might break.)
4. Take the lightsticks in graduated cylinders, lightsticks that are frozen and normal-room temperatured lightsticks to the dark room.
5. Use the Vernier LoggerPro program on the computer with Vernier LoggerFro Temperature probe and Light probe, to record and observe the temperature and illumination of the different temperated light stick.


Pictures:

DSC05427.JPG

When we were warming the water for the experiment.


DSC05442.JPG

Comparsion between the frozen lightstick and lightstick in the warm water.
As you can see, the lightstick in the warm water is brighter than the frozen one.

EXTRA EXPERIMENT(just for fun):



DSC05443.JPG
We opened up three different colored light sticks and poured the
liquid into the beaker.

DSC05450.JPG
After the winter break, we found out that all three colors are mixed together
and formed into something that looks like a lava lamp. It looked like jelly.


DSC05800.JPG
We tried to see what will happen if we boil the substance,
Slowly as it got heaten up, the round jelly-like substance started to move around,
This made it look more like the lava lamp.



DSC05801.JPG
As we heated the water, like a lava lamp, we noticed the chemicals
going upwards and forming bubbles, like oil.



Data:


Temperature (Celsius)
Illuminatiion (LUX)
Highest Point of Illumination (LUX)
Lowest Point of Illumination (LUX)
Room Temperature
23.7
66
116.1
20.1
Warm
31.2
235.8
340.7
114.7
Frozen
-17
7.9
8.3
0.2

Room Temperature:

jn1_ROOM_TEMP.JPG

Warm:

jn1WARM.JPG

Frozen:

jn1COLD.JPG

Evaluation: